United States of America
13"/35 (33 cm) Mark 1 and Mark 2
Updated 11 February 2015

In 1890 the Policy Board called for a variety of large caliber weapons, all the way up to 16" (40.3 cm).  This large a caliber was beyond US manufacturing capabilities of the time, as the largest size possible was 13"/35 (33 cm).

This gun was intended for short-range action against heavily armored targets and was fitted to the first true US battleship, the USS Indiana B-1.  This was the only gun of this caliber ever developed for the US Navy.

Background note:  The black powder propellants used for most of the 19th century burned very quickly, giving the projectiles a short, sharp kick.  With these kinds of propellants, the longer the barrel, the slower the muzzle velocity.  This was due to friction occurring after the propellant had completed combustion.  This is why heavy guns for most of the 19th century had such short barrels, some only 20 calibers long.  The late 1800s saw the development of brown or cocoa powder.  This burned more slowly, which allowed a longer barrel length and thus increased the muzzle velocity.  However, this propellant wasted much of its energy producing thick smoke.

Mark 1 Mod 0 consisted of 'A' tube, jacket and nine hoops.  Mark 1 Mod 1 had a nickel steel liner and eight hoops.  Mark 2 consisted of 'A' tube, jacket, seven hoops, and two locking rings.  One Mark 2 gun was converted to a 16"/28.8 (40.6 cm) Experimental gun.  More details and a photograph of this weapon may be found on the additional pictures page.

WNUS_13-35_mk1_Indiana_pic.jpg

USS Indiana B-1
Note the 8" (20.3 cm) twin mount on the right and the awning support across the turret
U.S. Naval Historical Center Photograph # NH 52653

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Click here for additional pictures
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Gun Characteristics
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Designation 13"/35 (33 cm) Mark 1
Ship Class Used On Indiana (B-1), Kearsage (B-5) and Illinois (B-7) classes
Date Of Design N/A
Date In Service 1895
Gun Weight 137,900 lbs. (62,550 kg) (including breech)
136,000 lbs. (61,690 kg) (without breech)
Gun Length oa N/A
Bore Length 455 in (11.557 m)
Rifling Length N/A
Grooves N/A
Lands N/A
Twist N/A
Chamber Volume N/A
Rate Of Fire about 1 round per minute
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Ammunition
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Type Bag
Projectile Types and Weights AP - 1,130 lbs. (512.6 kg)
Bursting Charge 13.6 lbs. (6.2 kg) Explosive D
22.5 lbs. (10.2 kg) Black Powder
Projectile Length N/A
Propellant Charge 180 lbs. (81.6 kg)
Muzzle Velocity 2,000 fps (610 mps)
Working Pressure 14.0 tons/in2 (2,205 kg/cm2)
Approximate Barrel Life N/A
Magazine capacity per gun 60 rounds
Note:  Propellant was in three equal bags.
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Range
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Elevation
With 1,130 lbs. (512.6 kg) Shell
Striking Velocity
Angle of Fall
9.5 degrees
10,000 yards (9,140 m)
1,327 fps (404 mps)
12.5
10.8 degrees
11,000 yards (10,060 m)
1,285 fps (392 mps)
21.5
11.5 degrees
11,500 yards (10,520 m)
1,267 fps (386 mps)
22.9
15 degrees
about 12,000 yards (11,000 m)
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Notes:

1) During the Battle of Santiago on 3 July 1898, the battleship Oregon (B-3) engaged in a running shoot with the Spanish cruiser Cristobal Colon.  Oregon's last shots traveled 9,500 yards (8,700 m) and landed just ahead of the Spanish ship, convincing her to surrender.  However, these rounds also "somewhat damaged" Oregon's guns due to the "high angle" (probably around +10 degrees) at which they were fired.

2) Time of flight for AP Shell with MV = 2,700 fps (823 mps)
   10,000 yards (9,140 m): 18.9 seconds
   11,000 yards (10,060 m):  21.3 seconds
   11,500 yards (10,520 m):  22.5 seconds


Armor Penetration with 1,130 lbs. (512.6 kg) AP Shell
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Range
Side Armor
Deck Armor
6,000 yards (5,490 m)
12.13" (308 mm)
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9,000 yards (8,230 m)
10.09" (256 mm)
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12,000 yards (10,920 m)
9.11" (231 mm)
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This data is from "Ordnance Data Sheets" of 1905.
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Range
Side Armor
Deck Armor
6,000 yards (5,490 m)
10.3" (262 mm)
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9,000 yards (8,230 m)
8.1" (206 mm)
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12,000 yards (10,920 m)
6.1" (155 mm)
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This data is from "Elements of US Naval Guns" of 1918 and is corrected for angle of fall.  It may also refer to harder armor than used for the 1905 data.
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Mount / Turret Data
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Designation Twin Turrets
   Indiana (2):  Mark 2
   Kearsage (2):  Mark 3
   Illinois (2):  Mark 4
Weight Mark 2:  440 tons
Mark 3:  712 tons
Mark 4:  503 tons
Elevation All:  -5 / +15 degrees
Rate of Elevation N/A
Train about -150 / +150 degrees
Rate of Train N/A
Gun Recoil N/A
Loading Angle Mark 2:  +10 degrees
Mark 3 and 4:  +2 degrees
Notes:

1) Defects in the design of the trunnions made it necessary to mount the guns so far back in the Mark 2 turrets that oversized gunports were necessary, negating much of the armor protection.

2) The Mark 3 had a superimposed twin 8"/35 (20.3 cm) mount on top of the twin 13" (33 cm) mount, accounting for its much heavier weight.

3) The Mark 2 used on the Indiana class could create a list as large as 5 degrees when trained directly abeam.  As the maximum elevation for these guns was +15 degrees, this list significantly reduced the maximum range.  Hoists were single stage, running directly from the shell rooms to the gun breeches.

4) The Mark 3 mounting used two 50 hp electric motors for training.  Elevation, hoists and chain-driven rammers were also electrically powered.  Run out in this mounting was a combination of spring and hydraulic cylinders.

5) The Mark 4 was a balanced design and so eliminated the listing problem.  The trunnions on the Mark 4 mountings were located close to the face plate, allowing for much smaller gunports and thus better protection.  In other respects, it was similar to the Mark 3 with electric power and direct hoists.

6) On 13 April 1906, exposed switch gear in the rear of one of the 13" (33 cm) mountings on Kearsarge (B-5) caused a powder burn, killing two officers and eight men, with four additional men being seriously injured.  As a corrective measure, all electrical equipment that might cause a spark hazard were removed from all USN mountings between 1907 and 1908.  Bulkheads were installed between the guns and breech gas ejectors were fitted to prevent flarebacks.

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Data from
"U.S. Battleships:  An Illustrated Design History" and "US Naval Weapons" both by Norman Friedman
"The Big Gun:  Battleship Main Armament 1860-1945" by Peter Hodges
"Battleships" by Paul Stillwell
and
Tony DiGiulian's personal files
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"Naval Ordnance - A Text Book" revised in 1915 by Lt. Cmdr. Roland I. Curtain and Lt. Cmdr. Thomas L. Johnson
"US Naval Guns - Marks and Modifications - Experimental Guns" dated 1956
"Range and Ballistic Tables 1935" by U.S. Department of Ordnance and Gunnery
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Special help from James P.
Page History

15 August 2008 - Benchmark
11 February 2015 - Added note regarding 16"/28.8 Mark A gun